To elaborate: Today the build.xml file on one of my projects got corrupted. Result: The Project was stuck building in production mode thus I was not able to properly debug it.
I found this thread on the Sencha forum that Explains a similar situation and helped me solve my problem:
http://www.sencha.com/forum/showthread.php?276036-Project-Settings-gt-Framework-gt-Sencha-Complete-Custom
Here is the solution in short:
Clean all of the CMD settings out of your project folder.To do that remove the following files:
.sencha/
build.xml
app.json